Switching device



Nov. 15, 1938. cHELl SWITCHING DEVICE Filed Deo. 2s, 1955 O V O O O O O OOO OOOOO OO OO O O OO ooooooooo Patented Nov. 15, 1938 PATENT OFFICE SWITCHING DEVICE Inkl Cheli.

Savona, Italy Application ummm, z3, 1935, semi Nq. 55,903 nl muy umn 15. 1935 4Claims.

This invention has for its object some new and improved means for selectively switching lamp panels or other means to be operated electrically.

The invention aims to provide a switching device adapted to be operated by elastic yielding pressure means, either pneumatic or mechanical ones, by employing metallic or otherwise cur rent-conducting stencils provided with protruding contact points adapted to selectively closea number of electric circuits including the lamps to be lighted on the panel.

The invention aims principally to eliminate all movable contact members, as slidable pins,

plungers and the like, thus -simplifying the r switching device and insuring a reliable operation under all conditions.

According to the invention this is obtained by providing an insulating board carrying the usual contact heads ntted at regular intervals and arranged in the usual manner like the lamps on the panel, and by connecting one end of each of these contact heads to the corresponding lamp on the panel, the other terminals of the lamps being connected through the source of electric f energy to the return Wire leading to a metallic part iitted near the switch board proper, the Whole being so itted that by yieldingly pressing a metallic plate, Vhaving protruding contacts, against the switch board, a number of circuits is closed through the said protruding contacts cf the plate, the body of the plate and a part of this plate contacting with the metallic part fitted near the switch board and connected with the return Wire.

'Ihe invention will be better understood by the following specification with reference to the attached drawing, in which:

Figure l is a transverse section through a device according to the invention operated by the pneumatic means;

Figure 2 shows diagrammatically how a plurality of devices according to Figure 1 can be connected to a common pressure line controlled by a motor operated distributing valve;

Figure 3v shows another embodiment of the invention by which a mechanical pressure instead of a. pneumatic one is employed;

Figure 4 shows a part of a contact stencil in which protruding contact points are embossed forming the letters RE; and

Figure 5 is a. section on line V--V of Figure 4.

The device according to the invention is substantially constituted by a board A of insulating material fitted at regular intervals with a number of metallic contacts B each of which is (CL 20G-46) connected to a terminal of the electric device to be operated and in the present instance with the lamps l to 'l arranged in parallel. In the preferred embodiment described and shown the insulating board A is enclosed in a metallic frame C to which the return wire M leads connected to the other terminals of the lamps I to 1 through the source of electric energy (secondary winding of transformer L).

As it will be apparent from the following description of the operation, it is essential that the free heads of contacts B lie under the plane oi the insulating surface on which the contact stencils K should bear.

The selective closure of the electric circuits is effected by means of contact stencils preferably constituted, as particularly shown in Figures 4 and 5, by metallic plates K, provided with a number of projecting points or embossings I stamped or otherwise fitted at like intervalsas the contacts B of the contact board A. If these stencils should serve to light a number of lamps on the lamp panel, the embossings are made on the stencils so as to reproduce the letters or other signs to be formed by the lighted lamps on the panel (cfr. letters RE in Figure 4).

In Figure 1 a pneuniatically operated device for use with the improved stencils shown in Figures 4 and 5 is shown. In the board A of insulating material a number of contacts B is embedded, as usual for swtchboards of this kind, each of which is connected through an insulated wire N to one of the terminals of the socket of a lamp (I to 1), the number and disposition of the contacts on the board being as usual the same as that of the lamps on the panel. The other terminals of all the lamps on the panel are connected to a common wire M (or eventually to the ground) which is connected through the source of electric current (secondary winding of transformer L) to the metallic frame C of the board A. Frame C together with board A constitute the bottom part of a kind of casing closed by a metallic cover D.

Frame C has upwardly projecting parts Y serving as abutment members for a pair of metallic angle bars E. Between the horizontal wings of angle bars E an insulating sheet F is iltted having a number of perforations corresponding to and arranged in the same manner as contacts B, the thickness of this insulating sheet being preferably a. little more than the height of the embossings I of stencil K.

The width of stencil K is substantially equal to the distance between the vertical wings of angle bars E, which thus serve as guide bars for the stencil.

The cover D is hollow and under its borders an elastic or otherwise yielding sheet G, made of rubber or the like, is attached. Thus between the cover D and the elastic sheet G an air chamber O is formed in communication with a source of pressure fluid through nipple H.

The operation of the device is as follows: Suitable stencils, previously prepared by embossing the projecting contact points I spaced like the contacts B on board A and forming the signs to be reproduced on the lamp panel are inserted between the angle bars E under the elastic sheet G. Each of the projecting points or embossings I enters thus a perforation oi the insulating sheet F and cornes to lie in front of a contact head B, but without touching it. By introducing a pressure fluid (air) through nipple H into chamber O, the elastic sheet presses the stencil K towards the board A, thus forcing the embossings I into contact with the corresponding contact heads B, while the borders of the metallic plate are forced into Contact with the horizontal wings of angle bars E. Thus a number of electric circuits are completed through embossings I, the corresponding contacts B, conductors N and lamps (|-4-5) return wire M, secondary winding of transformer L, frame C, bars E and stencil K, integral with embossings I.

A number of these devices may be arranged in parallel, as shown in Figure 2, connected to a common source of pressure iluid Q through a distributing valve P that can be of a rotary type r and eventually actuated by a motor R. By inserting in each of the devices a stencil bearing signs or iigures slightly displaced with regards to the adjacent ones, the eiect of moving pictures can be obtained on the lamp panel.

In Figure 3 a device is shown that in its lower part is substantially like to that shown in Figure 1. However, in this case the pressure on the stencil K is produced by mechanical means acting on the rigid plate T.

In the case as shown the pressure means are constituted by wing nuts U bearing on plate T and screwed on threaded stems V integral with frame C and passing through holes bored in the plate T. Of course, it is possible to employ other pressure means as cams, etc. However, in case a mechanical pressure is employed, it is necessary to insert between plate T and stencil K a somewhat yielding pad S, as a felt, a soit rubber sheet, an air cushion or the like. This prevents jamming oi points Iasainst contacts B and deteriora'- tion both of the stencils and of the contacts B.

It is apparent that the embodiments as shown and described are given only by way of example. Thus stencils may be made by inserting metallic points, or pins, into metallic or otherwise ccnductive plates; the device may be employed for selectively switching any kind of electric devices, other than-lamps, and the stencil may be pressed against the contact carrying board even by other means, as by electro-magnets.

It is to be understood therefore that the invention shall be limited only by the appended claims.

I claim:

1. A pattern switch for electric signs, including an insulating member, contacts extended through the member and exposed at the upper and lower ends, a box of conducting material in which the insulating member is positioned, angle plates secured to the box and in electrical contact therewith, said angle plates being arranged beyond the area of the insulating member, a compressible insulating strip overlying the insulating member and formed with openings in registry with the contacts in such member, said strip being positioned between the horizontal arms of the angle plates and having a thickness exceeding the thickness of such horizontal arms, a metallic stencil plate overlying and resting upon the insulating strip and positioned within and guided by the vertical arms of the angle plates, said stencil plate being formed with depending projections in line with the openings in the insulating strip, a pressure strip overlying the stencil plate, and means for creating pressure on the pressure strip to compress the insulating strip and permit the projections of the stencil plate to engage the contacts in the insulating member.

2. A construction as deilned in claim 1. wherein the depression of the stencil plate into engagement with the contacts causes the edges oi' said plate to engage the horizontal members of the angle plates for better electrical connection.

3. A construction as defined in claim 1, wherein the pressure means is pneumatic.

4. A construction as defined in claim l, wherein the pressure means is mechanical.

LUIGI CHELI. 

